A telecommunications eletrostatic discharge (ESD) requirement states that there should be no floating metal on a circuit pack. Floating metal acts as an antenna during an ESD discharge event. In addition, a floating piece of metal may contribute to a more severe secondary discharge. Floating metal can also be an electrical safety hazard. Therefore, a metal panel (faceplate) attached to a circuit pack must be grounded to earth when inserted into a subrack. The grounded faceplate also provides a path to ground from the ground layer of the circuit board.
FIG. 1. shows a conventional face plate assembly having a ground clip 12 that provides a ground path from the faceplate assembly to the subrack frame ground. The ground clip 12 is riveted to a metal face plate 60 attached to a circuit pack 80. A single rivet 13 secures the first end or base 14 of the ground clip to the face plate 60, while the opposite or free end 15 of the ground clip 12 is free to rotate about the axis of the rivet 13. The ground clip 12 includes a contact surface 16 that is offset from an axis of the rivet 13. The contact surface 16 is compliant in that it deflects downward as the circuit pack 80 is inserted in the subrack. Forces imparted on the contact surface 16 during insertion and extraction of the circuit pack 80 from the subrack 16 can cause the ground clip 12 to rotate or become skewed with respect to the face plate 60. If the ground clip becomes misaligned it can snag adjacent components, impairing the operability of the system.
Accordingly, improved apparatus and methods for grounding the face plates of circuit packs are desirable.